Society of Young Mathematicians - SYMs
A UK organization that motivates and encourages "all young people who enjoy mathematics." SYMS publishes articles, news, "things to do," calculator hints, book reviews, games, puzzles, and competitions in its newsletter, SymmetryPlus, and termly journal,
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Sudoku - Pappocom, aka Wayne Gould
Finish filling in the 9x9 grid so that every row, every column, and each of the nine 3x3 boxes contains the digits 1 through 9. Different from a magic square, this puzzle requires no arithmetic, only reasoning and logic to deduce which digit to put where.
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Technology PoWs - Math Forum
Challenges modeled on the Forum's Problems of the Week (PoWs) that take advantage of interactive mathematics tools. Students are invited to follow the link to "Submit your answer" to share their solutions, and then "self-mentor" using specially designed
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TierneyLab Puzzles - John Tierney
Challenging word problems that "put ideas in science to the test," from The New York Times' science columnist. Solve and comment on the puzzles and their extra credit extensions. See also Tierney's blog entries on mathematics.
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Tournament of Towns - Math Net, University of Toronto
A worldwide problem solving competition in mathematics. The contest attracts students of all mathematical interests and abilities with its inclusive rules and creative problems -- some as challenging as those of the International Mathematical Olympiad.
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Trimathlon
Site centered around a book featuring activities from number theory and geometry beyond the realm of the typical school curriculum. The site features a discussion forum, a sample online game (with others promised), and a periodic puzzler with hint.
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World Math Day - 3P Learning
The World Math Day website provides five- to eighteen-year olds with mental arithmetic questions to solve in competition with other math students from around the globe. Recent World Math Days, which take place in early March, have attracted participation
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Write Math with the Math Forum - Math Forum
A standards-aligned, grade-specific program to improve math problem solving. Engaging problems adapted from the Problems of the Week program have been correlated to state standards, math topics, and widely-used textbooks. A trial membership gives you
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